Animal carcass incinerator

ABSTRACT

An animal carcass incinerator designed to subject the entire external surface of the biomass material simultaneously to flame. The flame front burns inward toward the core of the material, greatly accelerating the burning process. Complete flame coverage of the biomass material is achieved by carefully shaping the internal surfaces of the incinerator. Burning gases are injected into a lower flame chamber. This lower flame chamber is bounded on its upper side by a grate, and on its remaining sides by the walls of the incinerator. Above the grate is a biomass chamber, where the animal carcasses or similar waste are deposited for incineration. The incinerator walls are lined with refractory insulating materials which incorporate a series of vertical flame channels. Likewise, the grate incorporates a series of vertical open channels. These channels are separated by raised ribs, which prevent the biomass materials from closing off the channels. The result is that even when the incinerator is jammed full of biomass materials, the burner flames still spread evenly around the entire external surface of the materials. A supplemental blower injects air to create a swirling pattern of flame within the biomass chamber.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

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MICROFICHE APPENDIX

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BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the field of waste disposal. Morespecifically, the invention comprises an incinerator capable ofincinerating biomass materials such as animal carcasses and the like.

2. Description of the Related Art

Incinerators in general, and organic waste incinerators in particular,have been in widespread use for decades. A typical example is shown inU.S. Pat. No. 5,699,745 to Kaehr (1997). The Kaehr device uses aninsulation-lined steel drum. As shown in FIG. 5, the generalconfiguration has a gas burner on one end (24) and an exhaust stack onthe other end (26).

A loading hatch is provided to load the biomass materials. The readerwill observe—particularly in FIG. 8—that the biomass material tends toburn in a linear fashion (from one end to the other). The Kaehr devicedoes not employ a grate, since prior art grates tend to deteriorate.Instead, it simply lets the residue fall to the bottom of the combustionchamber.

Similar devices are disclosed in U.S. Pat. No. 4,000,705 to Raber(1977), U.S. Pat. No. 5,799,597 to Kaehr (1998), and U.S. Pat. No.5,926,933 to Kaehr (1999). The incinerators shown in these patents arerepresentative of the prior art. The most significant aspect of thesedevices is that the biomass materials tend to burn in a linear fashion.The flame is located on one side of the material and the exhaust on theother. The biomass material begins burning on the side facing the flame,and the flame front progresses through the material.

The linear burning approach represents a limitation of the prior art.Much of the biomass material lies smoldering until the flame frontreaches it. Thus, the prior art devices are slow. They also tend toproduce incomplete combustion, resulting in excessive waste products.One approach to this problem has been to recombust the exhaust products(see U.S. Pat. No. 5,699,745), but this approach adds considerablecomplexity. A faster incinerator is certainly desirable.

Accordingly, the prior art devices are limited in that they:

-   -   1. Provide a relatively slow combustion process;    -   2. Require a multi-stage combustion process, adding considerable        complexity; and    -   3. Burn the biomass materials in a linear fashion.

BRIEF SUMMARY OF THE INVENTION

The present invention burns the entire external surface of the biomassmaterial simultaneously. The flame front burns inward toward the core ofthe material, greatly accelerating the burning process.

Complete flame coverage of the biomass material is achieved by carefullyshaping the internal surfaces of the incinerator. Burning gases areinjected into a lower flame chamber. This lower flame chamber is boundedon its upper side by a grate, and on its remaining sides by the walls ofthe incinerator. Above the grate is a biomass chamber, where the animalcarcasses or similar waste are deposited for incineration.

The incinerator walls are lined with refractory insulating materials.The walls incorporate a series of vertical flame channels. Likewise, thegrate incorporates a series of vertical open channels. These channelsare separated by raised ribs, which prevent the biomass materials fromclosing off the channels. The result is that even when the incineratoris jammed full of biomass materials, the burner flames still spreadevenly around the entire external surface of the materials. Asupplemental blower injects air to create a swirling pattern of flamewithin the biomass chamber, thereby covering the top portions of thebiomass material.

Accordingly, the present invention provides an animal carcassincinerator which:

-   -   1. Rapidly combusts biomass material;    -   2. Uses a single stage combustion process; and    -   3. Envelops the entire external surface of the biomass material        in flame.

DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is an isometric view, showing the proposed invention.

FIG. 2 is an isometric view, showing the proposed invention from anotherangle.

FIG. 3 is an isometric view, showing the proposed invention from stillanother angle.

FIG. 4 is an isometric view with a cutaway, showing some internalfeatures.

FIG. 4B is a detail view, showing the arrangement of the flame channels.

FIG. 5 is an isometric view with a cutaway, showing more internalfeatures.

FIG. 6 is an isomeric view, showing the grate.

FIG. 7 is a perspective view with cutaways, showing the operation of theinvention.

REFERENCE NUMERALS IN THE DRAWING 10 frame 12 shell 14 burner 16 exhauststack 18 main hatch 20 counterweight 22 main hatch hinge 24 blower 26blower intake 28 burner intake 30 clean-out hatch 32 clean-out hinge 34blower duct 36 burner jet 38 grate 40 flame channel 42 insulation 44grate notch 46 flame circulation 48 exhaust flow 50 burner plume 52lower flame chamber 54 biomass chamber 56 grate channel 58 air stream

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows the invention's primary external features. It consists of ahollow steel shell 12 supported by a generally rectangular frame 10.Burner 14 is placed at one end of shell 12, and exhaust stack 16 isplaced immediately adjacent the same end. Burner 14 is typically of thegas (commonly propane or methane) or fuel oil type. It features anintegral blower which pulls in ambient air through blower intake 28.

Main hatch 18 provides access to the interior of shell 12. As main hatch18 is heavy, it is provided with counterweight 20 to hold it in the openposition as shown. Main hatch 18 is attached to shell 12 by main hatchhinge 22.

Blower 24 is attached to shell 12 by blower duct 34. Blower 24 pulls inambient air through blower intake 26 and injects it into the interior ofshell 12.

FIG. 2 shows the invention from another angle. The reader will observethat the end of shell 12 which is opposite burner 14 is equipped withclean-out hatch 30. Clean-out hatch 30 is attached to shell 12 byclean-out hinge 32. The purpose of clean-out hatch 30 is to allow theuser to remove the residual ash after the incineration process iscomplete. Obviously, when burner 14 is operating, clean-out hatch 30must be dogged shut.

FIG. 2 also shows a better view of main hatch 18. It is necessary toheavily insulate the steel walls of shell 12. Otherwise, theincineration process would burn through the walls. Thus, as will bedescribed in more detail subsequently, shell 12 is lined with thickinsulation. The reader will observe that the swinging lid on main hatch18 consists of a piece of plate with an attached piece of insulation.The side walls of the insulation must be tapered so that they fit withinthe corresponding taper cut into the insulation inside shell 12. Thesame is true for clean-out hatch 30. As this approach is well known inthe prior art, it will not be described in greater detail.

FIG. 3 shows the invention from the side opposite the burner. In thisview, the reader will observe how counterweight 20 tends to hold openhatch 18 once it has swung near its fully open position. Hatch 18 willremain in this position until the user rotates it closed again. FIG. 3also shows how clean-out hatch 30 provides ready access to the lowerportion of the interior of shell 12. A user can insert a rake or smallhoe through this opening and pull the ashes remaining from theincineration process out.

FIG. 4 employs a cutaway to reveal some internal features of the device.The reader will observe the thin-walled nature of shell 12. Alsoapparent is the relative thickness of insulation 42. Grate 38 is placedin a horizontal plane within the lower portion of shell 12's interior.In order to aid visualization, the cutaway is carried through shell 12,insulation 42, grate 38, and exhaust stack 16.

The interior surfaces of insulation 42 are not smooth. Instead, they aremolded into a corrugated shape. A series of flame channels 40 extend upthe side walls (including the side wall which is cut away in the view).A series of flame channels 40 also extend up the interior surface of theend wall shown (the end opposite burner jet 36). There are, however, noflame channels on the wall in which burner jet 36 is mounted.

FIG. 4B shows the flame channels in greater detail. The reader willobserve that grate 38 is pierced by a series of grate channels 56. Theseallow flames to pass from beneath grate 38 up to the biomass sitting ontop. Likewise, the side wall shown is cut by a series of flame channels40. The same is true for the end wall (in the left of the view). Thelower portion of the end wall opens into clean-out hath 30 (shown justbelow grate 38). It is important to recall that grate 38 is shown with acutaway; i.e., it normally extends completely across the bottom regionof shell 12. Grate notch 44 is cut into the interior walls of insulation44. Grate 38 fits snugly within grate notch 44, with gravity holding itin place.

FIG. 5 better illustrates the interior surfaces of the wall opposite theburner. The series of vertical flame channels 40 are apparent. As is thecase with the side walls, the flame channels begin below grate 38 andextend well up into the interior of shell 12. The inner surface of theinsulation is solid between each flame channel, forming in effect a rib.The result is that the biomass materials within the incinerator will notbe able to occlude the flame channels.

FIG. 6 shows grate 38 standing alone (without the cutaway). The readerwill in this view more readily observe the shape of grate channels 56.

FIG. 7 is a perspective view with the entire shell and insulation cut inhalf in order to illustrate its internal operation. Grate 38 divides theinterior into lower flame chamber 52 and upper biomass chamber 54. Whenburner jet 36 is turned on, burner plume 50 erupts across lower flamechamber 52. The flames then shoot upward through grate channels 56. Theflames also shoot up the walls through flame channels 40. The bottom ofthe biomass material is exposed to flame through grate channels 56. Thesides of the biomass material are exposed to flames extending outwardfrom flame channels 40. Without more, however, the top of the biomassmaterial would be relatively unexposed.

Blower 24 is added to remedy this problem. Blower 24 injects air stream58 through blower duct 34. This jet of air tends to produce flamecirculation 46. Thus, the flames tend to roll over the top of thebiomass material, thereby completing a continuous envelope of flame.After rolling over the top, the spent combustion gases then rush out asexhaust flow 48.

Placing exhaust stack 16 on the same side as burner 14 is a significantfeature in the device's operation. Likewise, the provision of flamechannels 40 in its interior walls and grate channels 56 in grate 38combine to completely envelop the biomass material in flame. The resultis that the material is burning simultaneously on all sides. It istherefore consumed much more rapidly than would be the case if its isburned from one end to the other. In addition, since no part of thebiomass is left to smolder at relatively low temperature, the productionof offensive odors is greatly reduced.

Accordingly, the reader will appreciate that the proposed inventionprovides an animal carcass incinerator which:

-   -   1. Rapidly combusts biomass material;    -   2. Uses a single stage combustion process;    -   3. Envelops the entire external surface of the biomass material        in flame; and    -   4. Reduces the emission of offensive odors.

Although the preceding description contains significant detail, itshould not be construed as limiting the scope of the invention butrather as providing illustrations of the preferred embodiment of theinvention. Thus, the scope of the invention should be fixed by thefollowing claims, rather than by the examples given.

1. An incinerator for burning animal carcasses, comprising: a. aninsulated shell including an inner surface and an outer surface; b. agrate, placed horizontally within said insulated shell, so as to dividea space enclosed within said insulated shell into a lower flame chamberand an upper biomass chamber; c. means for introducing said animalcarcasses into said upper biomass chamber; d. a burner placed at a firstend of said insulated shell and beneath said grate; e. an exhaust stackplaced proximate said first end of said insulated shell and positionedso as to vent said upper biomass chamber to a surrounding atmosphere;and f. a plurality of channels cut into said inner surface of saidinsulated shell, wherein said channels are positioned to direct a flameproduced by said burner evenly around said inner surface of said shellas said flame proceeds from said lower flame chamber, into said upperbiomass chamber, around said animal carcasses, and out said exhauststack.
 2. A device as recited in claim 1 further comprising a blowerplaced proximate a second end of said insulated shell, and oriented todirect a stream of air against said flame so as to roll said flame oversaid animal carcasses.
 3. A device as recited in claim 1, wherein asecond end of said insulated shell opens into a clean out door, withsaid door being positioned beneath said grate, and wherein saidclean-out door is large enough to allow the removal of waste productsfrom said lower flame chamber.
 4. A device as recited in claim 1,wherein said grate includes a series of vertical grate channels whichallow the passage of said flame from said lower flame chamber to saidupper biomass chamber through said grate.
 5. A device as recited inclaim 1, wherein said means for introducing said animal carcasses intosaid upper biomass chamber comprises a main hatch opening through saidinsulated shell, with said main hatch being large enough to admit saidanimal carcasses.
 6. An incinerator for burning animal carcasses,comprising: a. an insulated shell including an inner surface and anouter surface, having a first end and a second end; b. a grate, placedhorizontally within said insulated shell, so as to divide a spaceenclosed within said insulated shell into a lower flame chamber and anupper biomass chamber; b. means for introducing said animal carcassesinto said upper biomass chamber; d. a burner placed at said first end ofsaid insulated shell and beneath said grate; e. an exhaust stack placedproximate said first end of said insulated shell and positioned so as tovent said upper biomass chamber to a surrounding atmosphere; and f. ablower, positioned proximate said second end of said insulated shell,and oriented to direct a stream of air downward and toward said firstend of said insulated shell.
 7. An incinerator as recited in claim 6,wherein said second end of said insulated shell opens into a clean outdoor, with said clean out door being positioned beneath said grate, andwherein said clean out door is large enough to allow the removal ofwaster products from said lower flame chamber.
 8. An incinerator asrecited in claim 6, wherein said grate includes a series of verticalgrate channels which allow the passage of said flame from said lowerflame chamber to said upper biomass chamber through said grate.
 9. Anincinerator as recited in claim 6, wherein said means for introducingsaid animal carcasses into said upper biomass chamber comprises a mainhatch opening through said insulated shell, with said main hatch beinglarge enough to admit said animal carcasses.
 10. An incinerator forburning animal carcasses, comprising: a. an insulated shell including aninner surface and an outer surface, having a first end and a second end;b. a grate, placed horizontally within said insulated shell, so as todivide a space enclosed within said insulated shell into a lower flamechamber and an upper biomass chamber; c. means for introducing saidanimal carcasses into said upper biomass chamber; d. a burner placed atsaid first end of said insulated shell and beneath said grate, so that aflame produced by said burner travels through said lower flame chamberand through said grate into said upper biomass chamber; e. an exhauststack placed proximate said first end of said insulated shell andpositioned so as to vent said upper biomass chamber to a surroundingatmosphere; and f. a blower, positioned proximate said second end ofsaid insulated shell, and oriented to direct a stream of air againstsaid flame so as to roll said flame over said animal carcasses.
 11. Anincinerator as recited in claim 10, wherein said second end of saidinsulated shell opens into a clean out door, with said clean out doorbeing positioned beneath said grate, and wherein said clean out door islarge enough to allow the removal of waster products from said lowerflame chamber.
 12. An incinerator as recited in claim 10, wherein saidgrate includes a series of vertical grate channels which allow thepassage of said flame from said lower flame chamber to said upperbiomass chamber through said grate.
 13. An incinerator as recited inclaim 10, wherein said means for introducing said animal carcasses intosaid upper biomass chamber comprises a main hatch opening through saidinsulated shell, with said main hatch being large enough to admit saidanimal carcasses.